The objective of this research is to define further in normal and allergic disease states the reaction mechanisms of formation, intrinsic and extrinsic modulating factors, physicochemical and character and nature of action of the biologically active products of the effector systems of acute inflammation (allergic) such as: the IgE-mediated release of histamine, slow reacting substance of anaphylaxis (SRS-A), the eosinophil chemotactic factor of anaphylaxis (ECF-A), and the platelet activating factor (PAF); the Hageman factor-dependent initiation of fibrinolysis and kinin generation; and the classical and alternative complement protein sequences. Although the principal goal is to assess the contribution, alone and in combination, of these various mediator systems to hypersensitivity states, the possible employment of such techniques to evaluate and direct therapeutic maneuvers serves as an additional stimulus.